Do you have to pay back your maternity pay if you don't return to work

My daughter-in-law works for a fashion chain. She is due to return to work next week. Her employer told her that she must return full time for six months or she will have to pay back her maternity pay. Before she took her maternity leave, she worked long shifts with unsociable hours. Her earliest start was 7am and latest finish was 11pm. She also worked weekends. She is going back full time and has asked for hours that will be more accomodating with child care. Her employers have refused and she will still have to do the same shifts as before. Is it right that she would have to pay her maternity pay back if she doesn't return.

She should read her employment contract/ the terms and conditions of her employment relating to maternity leave. Enhanced maternity pay (above statutory) may have to be repaid if your DIL doesn't return to work for the requisite amount of time. So statutory is quite basic but I received enhanced may pay of 6 months' full pay plus three months' half pay. I had to return for a minimum for 3 months (I think) otherwise I would have had to repay the difference between enhanced and statutory. I hope this makes sense.

The smp element is hers to keep - 6 weeks at 90% then about £135 for 26 weeks. Only additional occupational maternity pay topping Smp up is repayable and even then the conditions must be stated before going on maternity leave. It isn't uncommon to have to return to work for a minimum period to keep omp as it was intended to improve employee retention. She needs to check her employee handbook/intranet and any correspondence regarding her maternity leave.